This paper designs the physical model as geological conditions of XinZhi mine 2204 face of Huozhou Bureau of Mines in Shanxi province, it simulates the formation process and distribution of the mining rock fracture using simulation experiment of similar material, and researches the evolvement law of rock’s fracture network in caving zone, fractured zone using fractal geometry theory. The conclusion of the experiment indicates: with the advance of the working surface, the rock fracture develops from bottom to top, the different fracture network forms corresponds to the different push distance of the working surface, the latter network piles up the previous network, mining makes more complex distribution of rock fractures. The amount of overlying strata separation is three-stage separation law of development, including Initiating phase separation, Expansion phase separation and closed phase separation. Critical layer to any point along the separation experienced by the small → large → small and stable process of change. At the same time, the fractal dimension of the mining rock fracture goes through small to large, under the identical mining width, the fractal dimension of fractured zone is caving zone of 80% to 90%, at last, when the mining work is finished, the fractal dimension dropped to a more stable value.